Musicians' groups are to launch a national campaign to promote the study of music in school. Photograph: Richard Saker for the Guardian

Musicians have launched a national campaign to persuade ministers of the importance of studying music at school.

The coalition government announced in December that schools would be measured according to how many pupils achieved at least a C at GCSE in English, maths, two sciences, history or geography and a modern or ancient language.

Musicians are furious that the new measurement – known as the English Baccalaureate (Ebacc) – excludes music and other creative subjects, such as art and drama.

The Incorporated Society of Musicians (ISM) and Music Teacher magazine said they had already noticed that fewer pupils were taking music as a result.

The two organisations are calling on the public to write to MPs expressing their "deep concern" at the omission of music and other creative subjects from the Ebacc.

Deborah Annetts, chief executive of the ISM, said that by forgetting music, ministers had forgotten the "creative, social, academic, economic, emotional and intellectual benefits of an excellent music education".

Christopher Walters, editor of Music Teacher magazine said the Ebacc would "inevitably have negative consequences for any subjects that are excluded from it".

Ministers decided on the measurement partly out of concern that schools in low-income neighbourhoods were not encouraging their pupils to take traditional subjects, thus preventing them from obtaining places at top universities.

In May, schools minister Nick Gibb told MPs that the Ebacc was a "key component" in the "overall objective of closing the attainment gap between wealthier and poorer children"

"The committee fully supports the government's stated intention to improve the attainment of the poorest young people," the MPs argued. "However, the evidence is unclear as to whether entering more disadvantaged students for Ebacc subjects would necessarily make a significant contribution to this aim."

Japan and Singapore, whose education systems are lauded, have models that are similar to the Ebacc. But so does Germany, and its education system performs below the OECD average on some indicators, the MPs stated.

The report added: "The evidence which we received does not suggest a link … between the prescribed study of certain academic subjects and improved attainment and prospects for poorer students."

A spokesman from the Department for Education said the Ebacc existed so that "every single child gets a chance to study the core academic subjects which top universities demand". "But the Ebacc is not the be all and end all ... and should not be the limit of schools' ambitions for their pupils," he said.

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